CEYLON ALPHEID. 179 
The propodite has six spines, and the dactylos is well curved and 
single. The dimensions of the third leg are as follows . — 
i = 1386; 990 p = 2508; 581 
m = 3993; 1221 | d = 792; 198 
c = 3300; 726 | 
This form undoubtedly belongs to the obeso-manus group. 
General Distribution.—Maldives, Ceylon. 
ALPHEUS BUCEPHALUS, Coutiére. 
Alpheus crinitus, Coutiére. Bull. Soc. Entom., 1898. 
Alpheus bucephalus,Coutiére. Fauna of Mald. and Lacc., 1906. 
One specimen, from Trincomalee ; January, 1911. 
The rostrum is short and is not half as long as the first antennular 
article. The rostrum is continued with a median ridge which extends 
backwards between the orbits. 
The first and third antennular articles are equal, and both are 
slightly shorter than the median article. The scale is small, and 
only half the length of the first article. The peduncle is only five- 
sixths the length of the antennal peduncle, and equal in length to 
the antennal scale. 
The single specimen is small, and is too mutilated for accurate 
measurement. 
The dimensions of the chele are as follows :— 
e = 7:0 mm.; e' = 3:15 mm.; e? = 2:7 mm. 
The fingers are very short, and the palm is high in comparison to 
its length. Both upper and lower palmar borders are smooth. 
The second pereiopod possesses a long second segment to the 
carpos. The dimensions are as follows :— 
i = 2277; 462 | ot = 462; 346 
m = 2970; 330 6 — 660; 363 
ct = 643; 297 p == 1221; 429 
c2 = 1840; 330 d = 627; 165 
c3 = 462; 330 
The third pereiopod is very broad. There is a well-developed 
spine on the ischium. The meros broadens out distally into a very 
prominent spine on the lower side. The carpos has a blunt spine at 
the distal end of its lower border. The propodus is short and has 
about eight spines irregularly arranged on the lower side. The 
upper side is richly clothed with setz. The dactylos is strong and 
curved. Dimensions :— 
2310 ; 792 p = 990; 429 
1155; 495 d = 528; 165 
m 
Cc 
I 
General Distribution.—Indian Ocean, 
